Targets for charged particles are required for many applications. For example, they are required to produce an intense beam of fast neutrons. One target system for producing an intense beam of fast neutrons, which is described in Report AECL-2750, dated July 1967, by the Atomic Energy Commission of Canada, Ltd., involves proton bombardment of a column of lead-bismuth inside and completely enclosed by a pressurized Zircaloy tube. However, the neutrons produced directly, since they were thermal neutrons, required neutron multiplication around a Zircaloy tube that passed axially through a moderator vessel and shield, and a beam transport system that guided the proton beam to the top of a shield and thence downward into the target.